Feed-valve device



Aprilv 23, l929. c. c. FARMER FEED VALVE DEVICE;

Original Filed March 4, 1926 INVENTOR CLYD E C. FARM R AT.TORNEY Paamea apr. 23, i929.

,et i ,Y y1,709,904

'CLYDE c. FARMER, orri'rrsisuaeri, rnivivsvrivania, rissreivoi?. To 4THE ywnsrrive- HOUSE AIR'BRAKE COMPANY, or WILMERDING, rENNsYLvANiaA. CORPORATION OF PENNSYLVANIA.

original application led'VIarch 4, 1928, Serial No. 92,180. Divided,l and this application filed November.

j Serial No. 149,670. l l

This invention relates to feed or reducing vvalve devices and more particularly to the type employed in railway service for maintaining the fluid pressure in the brake pipe of the fluid pressure brake system.

The present application is a division of my application, Serial No. 92,180, filed March 4, 1926.

In the accompanying drawing; Fig. 1 is a central sectional View of a feed valve device embodying my improvements; Fig. 2 a section on the line 2 2 of Fig. 1.; and Fig. 8 an end view of the piston stem guiding means.

The feed valve device may comprise a casing 1 including a fluid pressure supply lportionV and a regulating portion. rlhe supply portion includes a piston 2 contained in piston chamber 3 and a slide valve 4, contained in valve chamber 5 and adapted to be operated by piston stem 6, which is connected to piston 2.

The regulating portion comprises a flexible diaphragm 7, subject on one side to the 'presn sure of an adjustable regulating spring 8. The stem 9 of a regulating valve 1() engages the opposite side of the diaphragm 7 and said valve is subject to the pressure of a coil spring 11.

According to one feature of my invention, a one piece bushing 12 is provided for receiving the piston 2 and the slide valve 4. Said bushing is machined to provide a seat for the slide valve 4 and to receive the piston 2, and is provided with an annular flange 13 intermediate the ends of the bushing, for engaging a gasket 14. The outer end of the bushing also engages a gasket 15. The bushing 12 Y is maintained in place by the cap plate 16 and an interposed gasket 17.

The outer end of the piston stem 6 is provided with a guide portion 18 which fits a machined bore in the bushing 12 and which is provided with a plurality of spiral grooves 19.

A passage 20, which communicates with piston chamber 8, leads through the cap plate 16 land communicates, through a choke plug 21, with a chamber 22 in the casing 1. The choke plug 21 is provided with a central restricted port 23 and radiating from said port stricted ports 24. Chamber 22 is connected 23 at a point intermediate the endsv arere` FEED-VALVE DEVICEL to the main reservoirf(not shown) through pipe 25. f

ur FPi-5er.;`

The passage'20 is connected to valve cham ber 26 containing the regulating valve 10. The regulating valve 10 is carried in a bushing 27 having 'a seat forthe valve and said bushing is providedwith van annular flange 28 adapted to engage a gasket 29.

' A cap nut 30 has screw-threaded engagement in the casing 1 and'is disposed in alineinent with the valve 10. .Said cap ,nutV is provided with an annular sleeve portion 31 which is adapted to engage the flange 28 of The one-piece bushing 12 may also be re" i moved when desired and a new one installed, by merely taking off the cap plate 16, the

`bushing being a sufficiently loose fitin the casing, to permit the bushing to be easily removed by the hands of the operator.

- The piston stem guide 18 is provided with l the spiral grooves 19, so that while the grooves provide communication between the chambers at the opposite sides of the guide portion and the consequent maintenance of balanced fluid pressures on the guide portion, the spiral arrangement of the grooves prevents possible cutting of grooves in the bushing by the to and fro movement of the guide portion when the feed valve is operating, and furthermore, any particles of dirt or metal will kbe caught in the spiral grooves and will thus be prevented from getting between thev guide portion and its'bore in the bushing, which would otherwise cause possible cutting of the guide surfaces.

The provision of a plurality of lrestricted ports 24k in the choke plug 21 is for the purpose of ensuringl an always open passage for the flow` of air. If one or more of the ports 21 should become clogged with dirt or parti- Y determined rate as fixed by the restricted area of a single port and the restricted area of the central port 23.

, Having now described myinvention, What I claim as newand desire to secure by Let ters Patent, is:

In a feed valve device, a casing, a regulating portion comprising a diaphragm, a valve having a stem operated by Vsaid diaphragm, a bushing containing said valve and stem and having an annular liange loosely mounted in` an annular recess in a Wall of said bushing, la plug having screw-threaded engagement in said casing, in alignment With and engaging said bushing, and a gasket disposed in said recess and interposed between said bushing and said Wall. y

In testimony whereof I have hereunto set my hand.

CLYVDE C. FARMER. e 

